In this work we present the manufacturing processes and results obtained from the characterization of heterojunction with intrinsic thin layer solar cells that include a heavily Ti ion implanted Si absorbing layer. The cells exhibit external circuit photocurrent at photon energies well below the Si bandgap. We discuss the origin of this below-bandgap photocurrent and the modifications in the hydrogenated amorphous intrinsic Si layer thickness to increase the open-circuit voltage.